Octoprint unresponsive after idling

What is the problem?
After not doing anything in octoprint / being in another tab for a minute, octoprint executes the first command sent only after a couple of seconds have passed. It only shows up in the terminal tab as sent after these few seconds too. If the command is sent trough API, it is instantaneous.
Subsequent commands all work immediately if I don't idle for too long.

I noticed the camera stream is most of the time loading then too, and I think the command gets send as soon as the camera stream is visible, but I have to recheck that.

What did you already try to solve it?
update Octoprint to 1.3.6, reading octoprint.log

Additional information about your setup (OctoPrint version, OctoPi version, printer, firmware, octoprint.log, serial.log or output on terminal tab, ...)
OctoPrint Version: 1.3.6
OctoPi: 0.14
printer: PrintIt 3020
firmware: repetier 1.0.0